AST, or aspartate aminotransferase, is one of the two liver enzymes. It is also known as serum glutamic-oxaloacetic transaminase, or SGOT. AST is a protein made by liver cells. When liver cells are damaged, AST leaks out into the bloodstream and the level of AST in the blood becomes elevated. AST is different from ALT because AST is found in parts of the body other than the liver—including the heart, kidneys, muscles, and brain. When cells in any of those parts of the body are damaged, AST can be elevated.

Explanation of test results:

A high AST level often means there is some liver damage, but it is not necessarily caused by hepatitis C. A high AST with a normal ALT may mean that the AST is coming from a different part of the body. It is important to realize that the AST level in most patients with hepatitis C goes up and down. The exact AST level does not tell you how much liver damage there is, or whether the liver is getting better or worse, and small changes should be expected. However, for patients receiving treatment for hepatitis C, it is helpful to see if the AST level goes down.

Other things to know:

• The AST level is not as helpful as the ALT level for checking the liver.
• Many patients with hepatitis C will have a normal AST level.
• Patients can have very severe liver disease or cirrhosis and still have a normal AST level.